Nonlocal labeling of paths in a single-photon interferometer
Matthew Pysher, Enrique J. Galvez, Kartik Misra, Kent R. Wilson, B. C. Melius, Mehul Malik · Physical Review A · 2005
We prepared polarization-entangled photon pairs and sent one of the photons through a Mach-Zehnder interferometer. The apparatus was arranged so that when going through each arm of the interferometer the pairs were in a different Bell state. The distinguishability of the interferometer paths was determined by projecting the entangled state of the two photons with a polarizer placed in the path of the photon that does not go through the interferometer. As a consequence, actions on the remote photon determined nonlocally the visibility of the interference pattern. We present a full theoretical analysis and experimental results that confirm the theoretical predictions.